Control gear, also referred to as ballast or operating device, are used for operating lamps such as light emitting diodes (LEDs) or fluorescent lamps. The control gear is configured to generate the necessary supply voltage for the lamps from a mains supply voltage, while also satisfying safety requirements. Further electrical circuits are used in conjunction with the control gear and the lamps.
These other electrical circuits can comprise sensors, such as movement sensors or brightness sensors. Operation of these sensors requires access to a supply voltage for the respective sensors. The sensors can be used, for example, for measuring physical parameters, which then send the recorded parameters to the control gear as an electrical sensor signal.
Appropriate supply lines are necessary for supplying a sensor with electricity, and additional circuits that require an energy supply are frequently needed for controlling the sensor and for external communication therewith. Normally, a converter used in the framework of the control gear generates the necessary low-voltage supply voltage supplied to the sensor via supply lines. Additional expenditure is required within the converter for generating this low-voltage supply voltage, comprising additional external connections, such as plug-in connectors, and additional supply lines between the converter and the sensor, as well as additional connecting lines for transmitting sensor data to the control gear. Alternatively, control gear inductors, in particular a transformer, normally a copper foil, are enveloped therein, to control the unavoidable stray fields. The power of these stray fields thus remains unused.
On the basis of the prior art described in the introductory portion of this description, the invention addresses the technological problem of improving the use of external circuits and control gear for lamps in a compact assembly, and improving the overall efficiency by using the energy contained in the stray fields.